I’d suggest you check your (probably poor) technique rather than trying to have a sly dig at those using cold only.
I’ve cleaned 3 nursing homes, outsides then insides, over the last week and whilst they were dirty my cold system has cleaned them without a single issue. I know this because I checked the externals whilst cleaning the internals.
Your obviously just not very good if you can’t clean to a good standard, stop blaming equipment.